Hyaluronic Acid (HA), also known as hyaluronan or hyaluronate, is a carbohydrate, more specifically a mucopolysaccharide occurring naturally throughout the human body. It can be several thousands of sugars (carbohydrates) long. When not bound to other molecules, it binds to water giving it a stiff viscous quality similar to "Jello". This viscous Gel is one of the most heavily researched substances in medicine today with thousands of trials mostly in the fields of orthopedics and eye surgery. Its function in the body is, amongst other things, to bind water and to lubricate movable parts of the body, such as joints and muscles. Its consistency and tissue-friendliness allows it to be beneficial in skin-care products as an excellent moisturizer. Because HA is one of the most hydrophilic (water-loving) molecules in nature with numerous benefits for the human body it can be described as "nature's moisturizer
If we compare the joints of the human body to an automobile engine, the joint fluid in the body mimics the oil in a car engine. At regular intervals we replace the oil in our car engines because the heat and friction breakdowns the oils viscosity. The oil becomes thinner and less able to protect the metal surfaces from excessive wear. Hyaluronic acid benefits our joints in the same way. As we age the viscosity of the joint fluid lessens. HA helps to maintain normal joint cushioning.
Structurally the scalp is identical to the skin tissue located throughout the body except it also contains about 100,000 hair follicles that give rise to hair. Actually the hair and the hair follicle are a derivative of skin tissue. There are two distinctive skin layers, one, the epidermis (outer layer) which gives rise to the protective shield of the body and the other, the dermal layer (deep layer) which makes up the bulk of the skin and is where the hair follicle is located. This dermal layer is composed of connective tissue and the connective tissue, with its gelatinous fluid like characteristics provides support, nourishes and hydrates the deep layers of the scalp. The result is healthy lustrous hair and a moisturized scalp. Again, all of this is made possible because of the presence of HA in the scalp.
Although Hyaluronic Acid (HA) can be found naturally in most every cell in the body, it is found in the greatest concentrations in the skin tissue. Almost 50% of the bodies HA is found here. It is found in both the deep underlying dermal areas as well as the visible epidermal top layers. Young skin is smooth and elastic and contains large amounts of HA that helps keep the skin stay young and healthy. The HA provides continuous moisture to the skin by binding up to 1000 times its weight in water. With age, the ability of the skin to produce HA decreases.
The skin is the largest organ in the body comprising about 15% of the body weight. Roughly 50% of the Hyaluronic Acid in our body is found in the skin. HA and Collagen are vital to maintaining the skin's layers and structure. It is the collagen that gives the skin its firmness but it is the HA that nourishes and hydrates the collagen. Imagine the collagen as the stretchy fibers that restore the skin back to shape when stretched. Collagen is like a rubber band but stretch that rubber band a million times, like what we do with our skin and without any moisture. Eventually that rubber band gets overstretched (saggy) and dried out and will most likely break. This is much the same way the collagen in our skin reacts leaving our skin in need of moisture. Now imagine that same rubber band stretched a million times while under water the whole time. Chances of that rubber band drying out and breaking are minimal. Consider the Hyaluronic Acid as the water that keeps the collagen moist and elastic. Collagen is continuously surrounded and nourished by the gelatinous HA substance. Young skin is smooth and highly elastic because it contains high concentrations of Hyaluronic Acid, which helps skin stay healthy. As we grow older, the body loses its ability to maintain this same concentration in the skin. With decreasing levels of HA in the skin, so goes the ability of the skin to hold water. The result, the skin becomes drier and loses its ability to maintain it's hydration. Hyaluronic acid acts as a space filler by binding to water and thus keeping the skin wrinkle-free.